On Self-Adaptive Mutation Restarts for Evolutionary Robotics with Real Rotorcraft
This addresses a specific limitation in evolutionary robotics for real-world applications like hexacopter control, but it is incremental as it extends existing restart methods to more complex algorithms.
The paper tackled the problem of self-adaptive mutation rates in evolutionary robotics for real rotorcraft, finding that individual-level restarts in population-based algorithms yield higher fitness solutions without stagnation, while population restarts provide more stable rate evolution.
Self-adaptive parameters are increasingly used in the field of Evolutionary Robotics, as they allow key evolutionary rates to vary autonomously in a context-sensitive manner throughout the optimisation process. A significant limitation to self-adaptive mutation is that rates can be set unfavourably, which hinders convergence. Rate restarts are typically employed to remedy this, but thus far have only been applied in Evolutionary Robotics for mutation-only algorithms. This paper focuses on the level at which evolutionary rate restarts are applied in population-based algorithms with more than 1 evolutionary operator. After testing on a real hexacopter hovering task, we conclude that individual-level restarting results in higher fitness solutions without fitness stagnation, and population restarts provide a more stable rate evolution. Without restarts, experiments can become stuck in suboptimal controller/rate combinations which can be difficult to escape from.